Adjustable electric lamp



Jan. 12, 1937. c. BIRDSEYE 2,067,344

I ADJUSTABLE ELECTRIC LAMP Filed Nov. 2, 1936 2 Sheets- Sheet 1 a4 IHVZWIOL cc mc 87' W 9%; k y W ADJUSTABLE ELECTRIC LAMP Filed Nov. 2, 1936 2 Sheets-Sheet 2 [Zn en 5011 Patented Jam E2 193? Ula-litdhh FAT actress antnsranma separate Application November 2, 1936, Serial Ne. 1%,786

M Claims.

This invention relates to electric lamps and particularly to those which employ in their structure a bulb carrying a reflecting surface for concentrating and directing the light from the lamp into a definite beam or field. In one aspect the invention comprises a base having the usual socket-fitting end portion together with an in termediate section which is flexible to the extent of permitting the position of the bulb to be angularly adjusted with respect to the socketfltting portion of the base. struction may be secured or otherwise fixed in an already-installed socket of any commercial construction and then adjusted either angularly or longitudinally so thatthe light emitted thereby shall be distributed most favorably for the requirements of the individual situation.

It is, of course, possible to install commercial sockets at any desired angle or to provide such sockets with external reflectors directing the field or beam of light in any desired direction, but when such an installation has been made, it is inflexible and the light distribution-cannot easily be changed to accommodate different require: ments. For example, an installation may-be made with the object of illuminating with the greatest intensity one end of the space in a show window, whereas conditions may change so that it becomes desirable to concentrate the light of the installation upon the center of the window space or along its rearwall or to create a spotlight jeffect. In the present" conditions such a change can be effected only by repositioning the sockets or providing a new set of external reflectors. The present invention provides an integral lamp structure adapted for any commercial socket and makes provision for the easy angular adjustment and readjustment of the lamp with its reflecting surfaces to secure. the desired distribution of its light.

s The lamp of my invention is also particularly useful in accommodating separate external reflectors which have been already installed, in that its construction facilitates and permits adjusting the lamps properly with respect to the focus of the reflectors. Thismay require a longitudinal or height-wise adjustment of the lamp with or without an angular adjustment and all such adjustments are within the range of movement permitted by the flexible section of the base herein disclosed.

The mechanical construction of the flexible portion of the base of my invention may take various forms. Satisfactory results1may be secured by elongating a hollow metal base of com- A lamp of this con-- (01. ltd-=32) mercial construction sumciently to include a corrugated or bellows section of copper or other easily flexed metal, or the base may be constructed to include a helix of non-resilient flexible wire, or a universal joint may be otherwise incorporated in the base in a location between its socket-fitting end portion and the portion thereof which is united to the glass of the bulb.

My invention includes within its scope not *only the complete electric lamp structure including a base by'which angular adjustment of the bulb may be effected, but it also includes the novel base herein shown per se.

As an additional feature my invention contemplates 2. base havinga flexible section through which one or more lead wires may be conducted and which have insulating protection, so that in flexing the base in adjusting the position of the bulb there will beno danger of short-circuiting the lead wire upon the inner walls of the base. Further, in bases wherein one of the lead wires is secured within the socket-fitting portion of the base it is contemplated that the lead wire, will be flexible and have provision for extension or elongation to guard against danger of break- 25 ing the lead wire in making any desired adjustment of the bulb position.

These and other features of the invention will be best understood and appreciated from the following description; of two preferred embodiments selected for\, purposes of illustration and shown in the accompanying drawings in which,-

Fig. l is a view in elevation, partly in section, of an incandescent lamp equipped with a base of my invention,

Fig. 2 is a similar fragmentary view showing a portion of the bulb in an angularl'y adjusted position,

Fig. 3 is a fragmentary view in elevation, partly in section, showing a modified form of base,

Fig. 4 is a view in elevation, partly in section, of an incandescent lamp having a modified form of base, 1 t

Fig. 5 is a fragmentary view showing the base elongated, and

Fig. 6 is an enlarged view of a base of modified construction.

Figure 7 is a sectional detail of the form shown in Figure 5; and

Figure 8 is a section similar to Figure 7, of the structure shown in Figure 6.

The bulb Ill herein shown may be of any usual or commercial construction equipped with an internal reflecting surface or a separate reflector to concentrate and deflnethe beam of light 55 source within the bulb. For example, the bulb may be provided as shown in Fig. 1 with an internal coating of metallic silver extending from the line of maximum bulb diameter to a line in the neck of the bulb, acting to hood the filament and direct the light of the lamp outwardly in a. concentrated beam through the bowl of the bulb. The bulb includes the usual glass mount i which is sealed into its neck and which supports the filament structure. The upper end of the mount constitutes a solid press l2 in which are embodied the two lead wires l3 and I4. An exhaust tube ll of usual construction is shown as located within the mount |,,this having been sealed at its lower end when the bulb was exhausted in the process of manufacturing the lamp.

The base shown in Fig. 1 comprises three portions having distinct functions. First, the usual threaded, socket-fitting end portion 20, second, the flexible corrugated intermediate portion 2|,

and third, the sleeve portion 22 which fits the glass neck of the bulb. The end threaded portion 20 is substantially rigid in its construction and may comprise sheet brass or the like molded or spun to present an external thread to be received ina socket. The intermediate or bellows portion 2|;may be constructed of a softer and more flexible metal such as copper and is shaped to include two or more rounded corrugations of the general construction employed in metallic bellows.

of dissimilar metal, may be of the same metal as the threaded end portion 20 but annealed so that it is softened and rendered flexible. The upper end of the base comprises a sleeve portion 22 which is shaped to surround the tapering end of the neck of the bulb and to contain a quantity of adhesive cement 23. Preferably-and as herein shown the end of the bulb neck may be provided with depressions or indentations l6 which provide anchorage for the cement 23., In any case the function of the upper portion of the base 22 is to form a fast and reliable union with the glass neck of the bulb. In addition to its flexing function the bellows section 2| provides an emcient-radiator for dissipating heat from the'lamp,

a useful characteristic particularly in high wat-' tage lamps.

One of the lead wires I3 is bent about the lower end or flange of the mount I I, brought out in the sleeve portion 22 of the base and united to the edge thereof by a drop of solder IS. The other lead wire I4 is brought down through the hollow base and' connected to a metallic button 25 which is insulated from the rest of the base in the usual manner. It is important to insulate the lead wire |4 within the base so that it cannot be moved into contact with the inner wall of the base when the section 2| is flexed. For this purpose the lead wire I4 is shown as encased in an insulating tube 24 from a point adjacent to the lower end of the mount II to a point adjacent its connection with the button 25, or in other words, for substantiallythe entire length of the base. Any suitable form of insulating protection adequate to prevent short circuiting of the lead wire against the base may be employed, such as tubing or beads of ceramic material, asbestos, glass, or the like. It is also to be noted that the insulated portion of the lead wire l4 may be coiled into the form of a loose helix or spring and thus provision is made Ol the 8X- The flexible'section 2|, instead of being.

emitted by the filament, not shown, or other light tension of the lead wire which is called for when the base is flexed.

As the lamp is initially constructed and distributed for use the base is symmetrically and concentrically disposed with reference to the axis of the bulb as shown in Fig. 1 and, the lamp may thus be screwed into any socket without special attention or consideration of any kind. Having once flxed the lamp 'in its socket any desired angular adjustment may now be secured by merely bending or tipping the bulb in the desired direction, as for example, as suggested in Fig. 2. Under these circumstances the corrugations of the flexible portion 2| are contracted on one side of the base and expanded on the other side, and an angular relation is established between the threaded end portion of the base and its sleeve portion 22, together with the bulb and all the parts carried thereby. As already noted, the section 2| is non-resilient although flexible, so that it will readily assume any adjusted position and when once adjustedwill maintain that position indefinitely. However, should further and different adjustment be desired this may be secured by merely bending or tipping the bulb in the desired direction.

One of many alternative constructions is illustrated in Fig. 3 in which is shown a base having a threaded end 30 and sleeve portions 32 of the character already described, but which portions are united to an intermediate portion or section 3| comprising a helix of flexible non-resilient wire. The helix illustrated comprises approximately five turns flattened at both ends and.

united by soldering or brazing to the upper and lower ends respectively of the sections 3|! and 32. The lead wire M which extends down through the base is connected to the metal button 35 and provided with an insulating tube 34 as described in connection with Fig. v1. The action of the base shown in Fig; 3 is similar to the action of the base already described. It may be inserted readily in any socket, and then the bulb may be angularly adjusted by flexing the turns of the helix in the section 3| of the base. The wire of the portion 3| of the base is shown in Fig. 3 as base comprises a rigid portion 50 threaded to fit the usual commercial socket, a flexible intermediate bellows portion 5| and-a flaring sleeve portion 52 which is united to the end of the neck of the bulb by cement 53. To supply a firm anchorage for the cement the neck of the bulb is provided with depressions or indentations 46. The lead wire 43 is conducted out through one side of the sleeve portion 52 and secured by a drop of solder as usual. The flexible bellows portion 5|, is herein shown as comprising four deep corrugations, these being formed of copper or other flexible metal. In this instance the entire outer surface of the bellows section 5| is covered with a thick coat of flexible bakelite varnish 56, thus insulating this portion of the base externally.

The lead wire 44 is conducted to the bottom of the base where it is soldered to the button 55. The portion. of this lead wire which passes through the base is shown as coiled in a helix 1 accuses and provided with an insulating cover M oi woven asbestos or other. insulating fabric. Its function is to prevent the lead wire from being short-circuited against the interior of the base when the portion M is flexed in adjusting the lamp. Provision is also made for preventing the lead wire from becoming wound about the exhaust tube ll? in continued flexing of the base. To this end a fibre washer 5b is threaded upon the end of the exhaust tube ti and provided at one side with a passage for the insulated lead wire till. It will be seen that the washer 5b acts as a spacer for the lead wire, keeping it concentrically at a fixed distance from the tube however the bellows portion hi or the base may be flexed.

In Fig. 5 the lamp of Fig. i is shown as adjusted longitudinally or height-wise with respect to the socket-fitting portion till ,by means of a symmetrical elongation or expansion of the corrugations of this portion. As alreadynoted this adjustment is useful in bringing the lamp to the focus of an external reflector already installed and this longitudinal adjustment may be combined or not with an angular adjustment as desired.

In some cases it may be desirable to insulate the flexible section of the base from its socketfitting end and such a construction is illustrated on a large scale in Fig. 6. In this construction the base comprises a rigid threaded portion 6t having the usual insulated button ti at its lower end. The flexible bellows portion 63 and the sleeve portion b ll are formed in one piece and connected to the threaded socket-fitting portion 60 through the medium of an insulating ring 62 of fibre or the like. The ring @2- is of suflicient width so that the threaded portion dd of the base may be connected thereto by one set of rivets while the flexible bellows portion tit is con-' nected thereto by a separate series of rivets. Accordingly, there is no electrical connection between these two portions of the base and the flexible portion remains dead. The lead wires 65 and bl in this construction are provided with flexible insulating tubes 66 of asbestos or the like. The lead wire as is conducted to the button t! and soldered thereto, whereas the lead wire 6i is conducted out between the flange of the threaded portion db and the insulating sleeve 62 and soldered to the socket-fitting portion of the base by a drop of solder 68. ,As in the base of Figs. 1 and 2 the base shown in Figs. 4 and 5 with its flexible section forms as a whole a closed tubular structure completely enclosing and protecting the end of the bulb neck and the lead wires emerging therefrom.

As already intimated mechanical joints may be substituted if desired for the flexible portion or section of the base in such manner as to-provide for the desired universal angular adjustment of the bulb with respect to the socket-fitting end of the base.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States, is:--

1. An electric reflector lamp designed to concentrate its light output into a predetermined field, having a bulb and a base including a rigid portion shaped to fit into a socket and a readily adjustable non-resilient flexible portion interposed between the bulb and said rigid portion,

whereby the lamp is given capacity for sustained angular adjustment with respect to its socket.

2. An electric reflector lamp designed to concentrate its light output into a predetermined field, having a bulb and a metallic base including a rigid socket-fitting portion, a sleeve portion fitting the neck of the bulb, and a closed tubular intermediate section which is flexible and nonresilient.

3. An electric reflector lamp having an adjustable bulb,and an integral metallic base having e sleeve portion fitted to the neck of the bulb, a rigid threaded end portion, and an intermediate flexible portion comprising a plurality of corrugatlons readily deformable in adjusting the bulb.

4. An electric lamp having a bulb containing a light source, a metallic base having a socketfltting portion initially disposed symmetrically with respect to the-axis of the bulb, and a closed tubular, non-resilient and flexible section which when flexed to position the bulb at an angle to said socket-fitting portion, serves to maintain the bulb in such position of angular adjustment, and a lead wire having insulating protection within the base.

5. An electric lamp having a reflecting bulb containing a light source, a metallic base having a rigid threaded end and an intermediate portion of flexible, non-resilient corrugations, and an insulated extensible lead wire secured in said threaded end.

6. An electric lamp having a bulb containing 7. An electric reflector lamp having a bulb containing a light source, a hollow metallic base having a threaded end and an intermediate nonresilient flexible section, a mount sealed into the neck of the bulb, a lead wire extending through portion'comprising a non-resilient flexible close wound, permanently deformable helix of non-resilient wire.

9. A high wattage electric lamp having a bulb containing a light source, and a metallic base including in its structure a rigid end portion shaped to be substantially enclosed within a socket, and an intermediate flexible section so located as to be disposed outside the socket and having. deep corrugations formed therein to facilitate heat radiation and give angular adjustment of the lamp with respect to its socket.

10. An electric lamp having a bulb containing a filament mount, lead wires and an exhaust tube sealed therein, and having a base with a non-resilient flexible section therein giving capacity for angular adjustment'to the lamp, and means within the base to prevent the lead wires from becoming entangled with the end of the exhausttube. v

11. An electric lamp having an adjustable bulb containing a filament mount, lead wires and an exhaust tube sealed in the mount, and a base with a flexible section therein giving adjustability to the lamp, and an insulating washer disposed concentrically about said tube and maintaining said lead wire in spaced relation or the lamp.

} 12. An electric lamp having a bulb containing a light source, and a base including in its structure a rigid, socket-fitting portion, and an in- I termediate bellows portion composed of flexible metal corrugations having an external coatingcf flexible insulating material.

13. An electric lamp having a bulb containing a light source, and a base including in its struchire a. metallic socket-fitting portion, and an i exposed bellows portion of flexible corrugations mechanically connected to the socket-fitting portion, electrically insulated therefrom and angu- 

